Bolt screwing depth in through holes and blind holes
Thread Content
Shown below in Bronze and Steel. What is the reason why through holes are screwed deeper than blind holes? The screwing depth should be determined by the tensile strength. The smaller the tensile strength, the deeper the screwing depth. Why does the mechanical manual stipulate that through holes and blind holes should be deeper when using the same material? Checked it online. , some people say that the bolts used for through holes and blind holes are different. I think it has nothing to do with the bolts used, but to do with the material. There is also a theory that the through-holes receive different forces when they are finally opened during processing. Anyway, it is not clear. I think it may be that the last bit of thread may not be an effective thread when it is opened. Can anyone with knowledge explain why the screwing depth is different?
When the nominal diameter is small, the 1.2 extra through holes can still be explained. But when the project diameter reaches 48, the screwing depth will be 10 inches short. Even the invalid threads are not as long as 10.